DHCPv4 is the only upper layer protocol that TraceWrangler can sanitize at the moment. IP and MAC addresses will be replaced based on the according settings set in their respective sections. Also, since there are a lot of DHCPv4 options and values, TraceWrangler only parses the most commonly used ones at the moment. This means that any option that it does not understand will be missing in the sanitized frame.
Sanitize FQDNs: right now, the only option to handle FQDNs is by replacing all characters with "x", as in the ICMPv6 section. This is necessary because the FQDN handling code does not yet exist for assembling frames. This will be part of the DNS assembler work that still needs to be done.